Exchange 2000

1. Backup stores and logs on old server. Shutdown old server (not down path location of logs and stores).
2. Install Windows on new server using same computer name and set up drives the same as old server with same folder names
3. Install Exchange using Setup /disasterrecovery mode.
4. Install SPs using same mode as setup.
5. Restore logs and databases to new server.
6. Mount stores
7. Check event logs etc.

http://support.microsoft.com/default.aspx?scid=kb;en-us;297289

if you mean migration then you can do it. Otherwise you can introduce another server in same admin group and then move mailbox and change sitefolderserver.

if you want to remove old server then you need to follow this link

http://support.microsoft.com/default.aspx?scid=kb;en-us;307917